Field of the Invention
The present invention relates to an apparatus configured to appropriately reading an image of a target object such as a paper document or a book, an image reading method, and a storage medium.
Description of the Related Art
A technology of digitalizing a target object such as a paper document or a book into image data or text data has been widespread. For the digitalization, a scanner configured to sandwich the target object between an original table and a pressure plate so as to read the target object, a document camera configured to readily acquire an image of the target object, and the like are used. The document camera includes a table on which the target object is to be placed and an imaging unit such as a camera, configured to image the target object on the table from above. When the target object placed on the table is a document or a book with distortion, e.g., a curl, it is important to image the target object while suppressing the distortion as much as possible. In Japanese Patent Application Laid-Open No. Hei 10-136194 and Japanese Patent Application Laid-Open No. 2013-247531, there is disclosed an apparatus configured to image an original document while a user holds down the document with hands or the fingers so as to suppress the distortion, erase an image of the hands or the fingers from an imaged image, and digitalize the imaged image.
When the target object is imaged while being held down with the hands or the fingers, the hands generally hold ends of the target object so as to prevent the hands or the fingers from being present in an imaged area as much as possible. Therefore, there is a possibility that distortion in a portion other than in a peripheral portion that is held down with the hands or the fingers cannot be sufficiently suppressed. For example, when a fold remains in the vicinity of the center of the document, the distortion in the vicinity of the fold cannot be sufficiently suppressed only by holding down both sides of the document. In this case, a character or the like on the read document is distorted. Therefore, when the imaged image is subjected to handwritten character recognition, image recognition, or form recognition, accuracy of recognition is lowered due to the distortion of the image. Therefore, the target object is required to be imaged while being held down at each distorted portion of the target object to suppress the distortion.